I have a long history with rotary powered cars. Namely, of not owning one. Over the past 15 years I’ve always danced around the idea. The last time I was close to purchasing one I opted for a MR2 Spyder instead. I found a deal on the lightweight, mid engine roadster that I couldn’t pass on. The RX8, was relatively new at the time and commanding new car prices. But I still dream about the silky smooth drivetrain in the Mazda even today.
Now that I’m talking race cars instead of daily drivers though, the landscape has become decidedly different. As such, I’m revisiting my affinity for rotaries and going a route a few are starting to stumble across. The performance value that has become the Mazda RX8.
There is a simple formula for fun at the track. Front engine and rear wheel drive. The inverse law of low budget racing states that ‘money spent is inversely proportional to fun.’ It’s a little more nuanced than that but if you want to race on a budget, that’s rule one. It is much more fun driving a well sorted Miata at the absolute ragged edge than it is driving a Corvette that you are ‘afraid to hurt’ due to repair costs. This is an issue I see repeatedly at the track and why the answer is always Miata when asked, ‘what car should I start with?’
That short list may very well grow to include the RX8 if this project pans out as planned.
To the point, have you seen the used market value of the RX8? I’m not sure when the rotary in the RX8 got cooties but I swear these owners are trying to give these cars away. I’m seeing running examples for as low as 3k and non running ones for under 1k. These aren’t just salvage titles either, these are non wrecked, intact cars.
Pro’s and Con’s
Let’s get the con’s out of the way. What makes the RX8 so special is also it’s one ‘weakness’. Namely the nature of the rotary motor in a daily driver. The Renesis motor in the RX8 is a naturally aspirated rotary motor that tends to stop enjoying it’s place in life around the 100k mile mark. Coupled with the thirsty nature of a rotary, it isn’t the most ideal for daily transportation. However, those issues are hardly a blip on the radar for a dedicated track car.
From my research it gets a lot better though. I spent some time at the Championships last year tracking down anyone campaigning an RX8. After speaking to a few, a consensus formed rather quickly. Everyone was very pleased with the way the car handles and performs in race conditions and weren’t really having issues in the way of engine trouble after the initial teething pains any racecar goes through. Generally being a motor refresh or replacement. To which I dug a little deeper finding out that a Mazda factory remanufactured motor could be picked up for just north of 3k.
That is cheap and to put things into perspective, if you are running in a spec series competitively with a piston motor, you are looking at rebuilding the engine every few seasons if not every. Comparing the 3k reman rotary to… let’s say a 944spec engine rebuild that regularly cost’s over 5k and you are looking at quite a good cost/use value with the rotary. And in a factory packaged power to weight ratio similar to an s2000.
Build and Goals
Now to the actual car. After much research, I picked up a 2006 RX8 6 speed for just under 1k. This is a non wrecked chassis with a very well maintained interior. One of the many, ‘the engine broke I don’t want to fix it’ examples flooding the used market.
This car will get converted into a full time racecar focusing on the principles of efficiency and lightness. The engine will remain stock starting with a Mazda reman unit to build a reliable and capable wheel to wheel and time trial car for exhibition outside of my usual 944spec competition.
Next I will strip the car to a dry, pre-cage weight for reference. (Coming Soon)